High precision U–Pb geochronology of the Lundy igneous complex: implications for North Atlantic volcanism and the far field Paleocene–Eocene ash record ...

• Main Authors: Lisica, Karlo, Augland, Lars E., Stevenson, John A., Jerram, Dougal A., Beresford-Browne, Adam, Jones, Morgan T.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Geological Society of London 2024
• Subjects: Geology; FOS: Earth and related environmental sciences; North Atlantic
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.7407977.v1; https://geolsoc.figshare.com/collections/High_precision_U_Pb_geochronology_of_the_Lundy_igneous_complex_implications_for_North_Atlantic_volcanism_and_the_far_field_Paleocene_Eocene_ash_record/7407977/1

Abstract: The Lundy Island granite (Bristol Channel, UK) is a felsic expression of the southernmost igneous centre of the North Atlantic Igneous Province (NAIP) that emplaced millions of km 3 of magma in the Paleogene. The distinctive S-type, peraluminous, two mica ± garnet ± tourmaline composition has led to the hypothesis that eruptions from the Lundy volcanic centre may be the source of thick felsic ash layers within the early Eocene Fur Formation (Denmark) that act as key marker horizons for the onset and duration of the Paleocene–Eocene Thermal Maximum (PETM). This study presents high-precision zircon U–Pb emplacement ages of 57.24 ± 0.11/0.12/0.13 Ma for the granite and 55.970 ± 0.021/0.030/0.070 Ma for a felsic ‘lundyite’ dyke. Trace and REE element patterns indicate close similarities between late-stage Lundy activity and ash layer ‘–33’ in Denmark that was deposited during the PETM carbon isotope excursion, suggesting that this centre is likely to be the source of this key ash horizon and that ...